display turns off when T41 gets warm

[pianowizard]

I just received a nice-looking T41 with the following specs:

ThinkPad T41 2373-8RU

P M 1.6GHz, 2x256MB = 512MB RAM, 60GB 7200rpm HDD, 14.1 XGA(1024X768) TFT LCD, 32MB ATI Radeon 7500, 24x-8x DVD, 802.11b, Modem(CDC), 1Gb Ethernet(LOM), UltraNav, Secure Chip, 6 cell Li-Ion battery, WinXP Pro

1) When the machine is cool, I can power it up and the screen turns on. Windows XP starts up properly, but after using the computer for about 5 minutes, the screen (both internal and external through VGA) turns all black (though not off) and the rest of the machine become unresponsive (e.g. Fn + F4 doesn't get it to stand by, Alt + F4 followed by "U" doesn't shut it down).

2) If I try to power up the machine when it has been recently used, everything seems to turn on (based on noise and LEDs) except for the screen.

3) The laptop behaves normally for at least an hour when I constantly keep it cool by putting it right in front of an air conditioner, and when I run PC Doctor, all components pass.

4) Putting a cooling pad under the laptop doesn't help much.

I suspect these problems are caused by the GPU getting too hot. Do you agree? This unit has a short fan. Do you think replacing it with a long fan would solve the problem?

[agarza]

No, I'd say the GPU is not the problem, Radeon 7500 do not tend to go hotter than a dedicated chip. I'd say either the GPU chip is damaged, or the inverter of the LCD screen is damaged somehow. Probably suspecting a general motherboard failure.

I suppose it's out of warranty your laptop. Spotting the real problem could be tricky. If the laptop gets unresponsive then possibly a motherboard failure. But you could check that booting from a live CD and see if windows is not creating the unresponsiveness

[pianowizard]

I know for sure that the inverter is good, and that XP isn't the culprit. Perhaps a general mobo failure, but how come it's rescued by keeping temperatures low?

I just installed NHC. It looks like the display turns off when the GPU has reached around 40 deg Celsius. By using NHC to force the fan to stay on, the lapop runs fine for quite a bit longer. So, I guess if I can keep the GPU constantly below ~40 deg C (104 deg F), this laptop will be quite useful. That's why I wonder if getting the long fan would help.

[gunston]

change to M10 Long fan and observe the result